We often use 'look after' and 'take care of' interchangeably, however to me there are subtle differences. Look after: implies to keep someone from trouble, watching over them, attending to their basic needs (feeding, washing, providing shelter etc), like a guardian. Take care: suggests protecting someone, providing love and care. (This seems more maternal to me). I might hire a pet sitter to look after my pets while I am on holiday. But as an owner, my responsibility is to take care of my pets. (I shouldn't only protect them, but also provide love and care)

Both are correct! And the term “maternity leave” can refer to before or after the birth—it refers in general to the time you take off work to have a child

Both are correct Ma'am.

Can we practice English together?

First of all if you are in maternity leave that means your children is not born yet. And in case you have another child then you can say. I am taking care of my children/ child .