Q&A: 15-month-old hitting and dealing with your mother

Amy writes:

"I have a 15 month old son who is such a love.  It has been love at first sight since the beginning.  We spend almost all of our time together.  My boyfriend has a very unpredictable schedule so we have days when it is all three of us but for the most part it is always me & child together (which i love so much).  Recently he has started slapping me or hitting me in the face.  Mostly it is when he is tired, at the end of his little rope... like on the final walk home from a morning out or before bed as we lie in bed together nursing and then if he isn't going down he gets a little excited and slaps me or (this is great) when i am carrying him up 4 or 5 flights of stairs with grocery bags in each hand with him in an ergo carrier.  I do think it has something to do with unexpended body energy and tired state of mind for the most part but some days i really do have to go to the post office and the grocery store and he has to come with me.  Anyway, besides angering me to no end, it's really embarrassing to be slapped in the face by a toddler and then hear laughing as I say NO.   Or try to catch his hands before he does it again and have him laughing the whole time.  I have experimented with different no's:  Holding his hands down and firmly saying no.  He cries (because he hates to be restrained at all) and then hugs me. Which all feels bad.  Trying a surprise "NO!" in a louder, stronger tone which feels awful and is also really coming from an anger place and not something I believe in when setting boundaries for a baby.  He laughs.  I think its nervous laughter because I never use that tone or volume of voice with him but maybe he is just laughing at me.
To compound matters, I am out of the country for a bit and my mother came to visit.  It has taken a while for her to completely accept the way that i am raising the baby -- extended breastfeeding, breastfeeding on demand, no CIO, no crib, no stroller until recently (one reason is just logistical, easier to navigate new york city with a baby on you rather than pushing a stroller but I also love having him near and up high with me), etc. etc. ...Anyway, she is pretty much completely on board with me now as he has turned out to be such a happy, loving, independent, funny, wonderful person... there's not much to fight me about.  But when it comes to the hitting me, well it makes me feel like a pushover in front of her, that my parenting is somehow too laid back or child centered.  She suggests growling "No" loudly and basically scaring him into behaving. 
What I really don't like is reacting out of anger.  My mother really did get angry, angry at us when we were children.  She hit us (now she is horrified that she did such a thing), yelled & screamed at us when we pushed limits or broke rules and really we were very scared of her when she was angry.  It never stopped us from doing what we were going to do, I think, but it just made us better at not being caught.  I think she had a short fuse due to all of the turmoil that was happening in our lives.  I understand & forgive it all.   We're really close and can talk about all of these things for the most part but her first instincts in terms of parenting advice always seem a little insane to me. obviously, having a child brings up all of these things for me.  How do I want to do it?  How do I set boundaries with out using FEAR and anger.  The baby is 15 months old.  He's a baby.  Being angry at a baby is one of the worst feelings in the world.   I think I need a good plan to deal with this slapping so that I don't allow it to fester and then blow up at him (which has happened a couple of times, my worst parenting moments to date) and also to set me on the right track for being strong and loving, setting boundaries with love."
There are three issues in this email: the hitting stage some toddlers go through, setting firm limits without being punitive, and negotiating your relationship with your own mother. Let's do the first one and part of the second today, and then start a new topic about dealing with your parents tomorrow.
I don't have an answer for the hitting issue. When there's a clear reason a behavior is happening, you can address it, but I'm not sure the reasons young toddlers hit is always that clear-cut. If he were closer to 2 years old, he'd probably be hitting out of anger and frustration, so giving him another way to channel those feelings and at the same time helping him communicate better would probably curb the hitting quickly. But it's not usually so clear-cut with a young toddler (under 18 months). Sometimes they hit out of tiredness, sometimes out of frustration, but sometimes they just hit because they like the way it feels, or think it's funny.
I think the best thing you can do is try to keep him out of situations that provoke it (figure out if there's a better time of day to do errands and a worse time, and try to avoid the worse time). At the same time, think about your feelings. What is it that makes you feel so embarrassed about being hit by him? Is this something that makes you feel worse than the other stuff he does that you don't like? It seems like this hit (ha ha) a particular nerve. I'm wondering if maybe this was an issue your mom had particular problems with and was extra-punitive with you about. Or maybe this reverberates in you because you did get spanked as a kid. (That one sounds veeery familiar to me. Getting hit by my younger one shot right through to my psyche, and I think it's because I felt so enraged when I'd get spanked as a kid.)
At any rate, it's probably just a phase, so knowing that, it's not a do-or-die situation to curb the behavior, as it'll pass anyway. So you could use this time to figure out how you're going to deal with misbehavior that sparks strong feelings in you.
The other thing is to figure out what's going to work with him. I did do the roaring thing with my older son, and it stopped him in his tracks but after a quick hug he moved on (without doing the behavior I'd roared to stop). In other words, it worked the way it needed to, without making him feel bad (just startled!). My younger one, though, gets so upset if spoken harshly to, which makes it awful if he runs away someplace he's not supposed to, because there's no way to react except to scream "NO!"" BUt once we've talked about it, he does a great job with role-playing and pretending to be ä cat who stops at the curb" or whatever.
In other words, it's all a process. And part of getting to know your child and yourself. And you're going to make mistakes. And you're going to have to do things that you don't like (like making your kid cry when you scream "NO!" to stop him from running into the street). And your kid will piss you off, and your kid will piss you off. But you'll work your way through it together.
I'm really hoping Sharon Silver has some comments about all this (especially the hitting), because I've never been good with figuring out what to do when the kid really does think it's just fun.
Anyone else?