For your wife's sanity, please see if you can get a seat for your toddler on the outbound too. She will appreciate not having a toddler moving about, eating, sleeping and (if still in nappies) pooping on her for the trip. She'll be able to eat and watch her own IFE as well as have more space and not intrude quite so often into the space of her row-mates.
There are some serious brownie points to be had here.