Parvati wouldn't put it in writing, no. She wouldn't want to endanger the kid! In fact, she'll probably have to change his name since Susan announced his name with his birth before she was brutally murdered. I'll write a narrative about her wanting a baby as soon as the holiday chaos passes and I have time to think. Is McG NPCed? Can I puppet her a teeny bit, or would someone like to write her for me? I could just vague it up in thoughts like "tried to talk to McG, nothing came of it, then went to the orphanage" sort of narrative.
I'll work on THE somehow, some way bit. But I assume Parvati has been fussing over Wesley around any babysitting she's done. And got all maternal at Seamus anytime they did the switch off ("he likes this position best" and "take these wind chimes, they're for protection and the sound puts him to sleep", etc etc). So she's given Seamus reason enough to go to bat for her, hopefully.