On every season of The Bachelor/ette, there's always one guy or gal that wants to take things slower than the other contestants. I get it — I'm a late bloomer myself, and I like to be really sure about things. So does Peter, who has expressed that though he really cares for Rachel, he doesn't know if he can propose just yet. Though some could be wary of that, Rachel's mom praised Peter's slow-moving attitude on The Bachelorette.
In a normal relationship, most people would take the traditional milestones of "I love you" and meeting the family a little slower than Peter is on The Bachelorette, and Rachel's family, having already done this stuff when Rachel took Nick Viall home on The Bachelor, seemed wary of going through it again. Even Rachel was hesitant because Peter was all, "I like you but I can't put a ring on it yet." Luckily, Rachel's mother brought some actual sanity into the episode, and she encouraged Peter to be honest about his feelings. Peter confessed that he has very strong, I-miss-you-when-you're-gone, don't-wanna-miss-a-thing feelings about Rachel, but is a little slow to pick up on the proposal part (six weeks is hella slow, guys *rolls eyes*). I think if Rachel's mother could have stood up and applauded, she would have. Instead, she praised Peter for knowing himself well enough to know that he doesn't want to rush this relationship.
I don't know that any family would be 100 on their daughter or son being on The Bachelor/ette, and a methodical, thoughtful man like Peter is as good as it gets in terms of what would most resemble a real-life courtship. To me, it's weird that Bryan (and many others along the way) is claiming he's deeply loved Rachel since their first one-on-one. That's not real. What real is a deep, slow, getting-to-know-you process, and Rachel's mom sees that. Peter is a real deal on The Bachelorette, and he's entitled to move at his own pace.