parents looking for other parents

Welcome to Germany. I am a clown and juggler living in Stuttgart so I know the performing scene although I don’t work in variety shows. But I can possibly give advice about Germany, immigration or performing here in context of such work. Unfortunately I don’t know Hannover well enough to give any specific advice about it. Hard to say where the kids can best socialize other than finding well frequented parks although the weather this time of year is pretty hit or miss. 

Not sure if nursery schools usually take kids for such a short time and/or for maybe just some hours  once or twice a week but it might be a possibility. Some even have an emphasis on English being spoken. For the German kids it gives them a head start in learning English since as you’ve noticed they usually don’t have any exposure before attending school. I think such places really like to have kids as well that speak English as a native language, so they might make special conditions to accommodate you.

I am setting a link to a site that gives information about all of the nursery schools in the Hannover area. Unfortunately it is only in German so you would probably need help to navigate it. They group kids into up to 3 - or older than 3, then one indicates which neighborhoods come in question. 

[link moderated]

I wanted to mention that the link I posted in my above comment accidentally got deleted by the administrators. They offered to restore it but then I didn't find it in the internet. But one can find out information about nursery schools and day care and other services associated with kids on the Hannover city website.