New to Athens - looking for a playgroup

Hello. My husband and I moved to Athens from London two weeks ago with our two children (aged 6 and 3 years). My older child is settling in at school and making friends happily. I am at home with the younger one and we are both looking to make some English-speaking friends (whilst we are trying to learn some basic Greek!). Are there any play groups/ parent and child meetings that anyone could recommend please? Ideally in Kifissia - I am still getting to grips with the driving and don't feel brave enough to venture too far from home...
Many thanks.