Hey, I was rereading this looking for recs, and the Vulcan bit reminded me: have you read Macedon and J's Jeu-Parti? It doesn't have Vulcan toddlers[*], but the third part does have Jake Sisko's human toddler daughter being adorable and plausibly three years old, and there's a Vulcan character who's an early childhood education specialist.

Animal harm advisory: brief mention of a newt's death.
Location of the mother: being a gigantic stereotype of an unfeeling career woman.

[*] SPOILER: until the epilogue.