Ashley Tisdale looks like she's forming a new mom group with Haylie Duff ... because their families are breaking bread following the "toxic mom group" drama.

Check out these photos of Ashley and Haylie leaving an Italian restaurant in Malibu with their kiddos in tow ... no toxicity here, or so it seems.

Ashley and Haylie continuing to hang out is interesting ... their kids had a play date this week ... and it raised eyebrows because Haylie's sister, Hilary Duff, is thought to be involved in the "toxic mom group" Ashley groused about -- at least that's the online theory.

Fans also speculated Mandy Moore and Meghan Trainor were in the mean-girl mom circle Ashley decided to quit ... and the speculation only deepened when Hilary's husband Matthew Koma appeared to take a swipe at Ashley on social media.

Another layer to this ... a long-standing narrative is that Haylie and Hilary are estranged. The sisters haven't been seen together in years and there's speculation Hilary sings about their allegedly fractured relationship in her new song, "We Don't Talk," which she's performing on her new tour.

Hilary and Haylie have been mum on their relationship, and Hilary hasn't confirmed if the new song is in fact about her sister ... but Haylie hanging out with Ashley seems to speak volumes.

For the record, though, Ashley's rep previously told us fans were looking too deep into her "toxic mom group" essay, and their theories missed the mark.