Hi Joseph

Strictly anecdotal and observational, but teaching a second language to a small child should not end up hindering him/her in the learning of their first language. At least in the long run. Though there may be some occasional cross-over of language(s).

Many Jewish children attend classes after their "normal" School day, to learn Hebrew. They seem to cope OK, and have done for centuries.

A child whose (foreign-born) parents speak one language at home, will often find that their child speaks another when s/he is out playing with friends in the neighbourhood. One sister-in-law became a fluent bi-lingual when she was younger, although she did tend to switch languages and substitute words from one or other of her two tongues when she couldn't remember it in the one she was speaking.

It is easier for a young(er) child to acquire new languages, than for an older one or an adult.

Keep going with your lessons. As Is. Good luck.

AMonk