my filly is 5 months old and I have her in with my anceint gelding, who's going blind, he loves her and they share a fence line with her dam. I don't have any issues. I also have her yearling who has been a gelding for almost 2 weeks now out with another gelding and they have shared a fence line with no issues. Start gradually taking her away from mom and you shouldn't have too many issues, start with an hour or two a day if you can, also if you are feeding mom, cut her food way down for a few weeks, I didn't do that and I ended up with a mare with mastitis last year. This year I cut her food out completely, she wasn't bred back and started working her. I'd take mom out, leaving baby with her friend drive mom for a bit and then put them back, then I'd put mom in another pasture for a while and then finally seperated them completely.
Karen