Yes/Chad/Lay some foundation for your future plans
You aren't going to get a better opportunity to fine tune the changes to your family than at the dining table. That said, some of the changes that you want to make might seem pretty bizarre; making it challenging to make them. Maybe you should fix that first.
"Hey everyone," you say, "I'm going through a bit of a weird patch in my life, so if I say or do anything weird could you guys treat it like it was normal, and not be mad at me or anything?" You haven't tried the power out on multiple people, so you aren't sure what to expect.
"Of course, honey," says your mom.
"Yeah totally," says Gwen, "but you were always a weird poser."
"Sure," says Emily.
Your super hearing even picks up Bree upstairs saying, "Okay . . . wait why did I just say okay?"
Interesting, not only does it work on groups, but they don't even have to be able to hear you? Sweet!
"You guys are great. Anyway, there's a good chance I'll want to have sexual relationships with everyone in the family, and even more girls outside of the family. Is everyone okay with that?"
"Yeah," says Emily, "that's fine with me."
"Yes I suppose," says your mother, "but Emily, and especially Bree are really young. You need to be careful with them, and not hurt them physically or emotionally."
"Sure poser," says Gwen, "I bet this means you want my best friend Maria, huh? All the boys want her."
On the stairs Bree says, "Yeah okay," then entering the kitchen continues, "wait, what am I agreeing to?"
"Chad is going to have a harem and we're all in it," says Gwen.
"Cool," says Bree, "what's a harem?"
"Gwen really," admonishes your mother, "harem indeed! Bree a harem is something the Sultan's in the Middle East used to have. They would have a lot of women that they did adult stuff with like making babies. We're going to be a bit more modern than all that. We're just having an open polyamorous relationship with him. And before you ask, polyamourous means being in love with more than one person at once."
"I get to have a baby?" asks Bree, nearly squealing.
"Eventually," says your mother, "your body is too young right now. There are other concerns. If he wants to start getting a lot of girls pregnant, he's going to have to start bringing in a lot of money. So Chad, before you go knocking up half the neighborhood I expect you to finish college and get a good job. Use protection. Do you understand young man?"
Your mother handling the breeding of multiple women like you were just going out on a date strikes you as amusing. "Yes, ma'am . . . but what about the baby we're probably going to have."
You mother blushes deeply, "Well, what's done is done."
"I'm going to have a baby brother or sister?" asks Bree.
". . . and nephew or niece at the same time," chimes in Gwen.
"Nothing is definite," says your embarrassed mother, "but there's a good chance, yes."
"Can Chad get me pregnant next?" asks Emily.
"Weren't you listening to a word I said young lady?" says your mom sternly. "No more babies until he can provide for them."
"I think Emily would look really hot with a pregnant belly. Don't you guys think?"
Everyone says yes almost simultaneously, you mother continuing, "but I stand firm by my decision. It's settled, enough talk about babies. It's time for school, and I have to get to work. Don't forget about the groceries, Chad."
"Sure thing, mom."
Off to school?