The Williams sisters set up a Wimbledon final clash on Saturday with Venus admitting they rely on each other's advice to constantly improve their respective games.
Venus held off the determined challenge of fifth seed Elena Dementieva to advance to her seventh final at the All England Club, powering through the opening set and being pushed all the way in the second before sealing a 6-1 7-6 (7-3) victory.
The four-time champion then watched Serena defeat China's Zheng Jie 6-2 7-6 (7-5) in the day's second semi-final on Centre Court to make the final a family affair.
The pair will combine in Friday's doubles semi-final before heading back to the rented apartment they have been sharing for the fortnight.
"I think that we share even more things together off the court," Venus said when asked about any changes in their relationship down the years.
"We definitely rely on each other's advice even more."
"I was a big sister. I was telling her, 'Never make mistakes'. So I think sometimes it put pressure on her to be perfect, too."
"Not that I'm perfect, but I'm just really like a nerd! She wasn't exactly that way, so I think we both now know our roles in the relationship and we support each other."
"She's definitely matured in a lot of ways. I don't really worry about her that much. I respect the decisions that she's going to make."
"On the court, she's always Serena Williams. She's tenacious. She's got every shot no matter what. You can't bet against her."
Serena was made to work a little harder by Chinese wildcard Zheng, saving a set point before a double fault from her opponent sealed the match.
The younger sister refuted criticism there had not yet been a classic match between the pair.
"I think you're stating opinions," Serena said.
"I've had a very classic grand slam final against her at the Australian Open. It was three extremely tough sets. It was a long match."
"It wasn't very easy. And I think also at the US Open. It was fast, but it was a very high-quality tennis."
"So I look forward to it."
"I was really excited because I feel like it's just coming together now. My game is doing better, as well. I was serving better and moving better."
"I think anyone can say that to be in a grand slam final is great. Everyone wants to take it to the next level."