My male dog got my neighbors dog pregnant?

Well as I was on vacation my male toy poodle maltese mix who in unfixed (yes i know irresponsible) stayed with my neighbor a couple house down .she has a papillon pomeranian mix who in unfixed also so while the 2 weeks i was gone they mated and now she is pregnant i know this because my neighbor showed me her vet bills .my question is what do i have to do to help support my neighbor ? i do agree on going half on everything .what else though to be emotionally ready?