Alec Baldwin and his wife, Hilaria Baldwin, welcomed a baby daughter last week named Carmen Gabriela.
Alec's 17-year-old model daughter, Ireland, welcomed her new half-sister by posting a note to Instagram that read "I have a f------ sister!!!"
Ireland, whose mom is Kim Basinger, later wrote a long, revealing blog post on her Tumblr account, offering advice for her new little sis on how to navigate the world.
"I love you, Carmen. You have been born into one crazy family," Ireland warns. "You are both lucky and cursed at the same time."
Ireland was the recipient of her father's much publicized, hateful voicemails in 2011 when he called her a "rude, thoughtless little pig" during a custody battle.
"Parents are cray cray and sometimes you want to just put a muzzle on it," she wrote in the post. "BUT they don't make muzzles for parents and again, it just isn't worth it. Just say you're sorry and leave it at that."
Despite now having a close relationship with her famous parents, she admits their journey has had its bumps.
"I have said many things to our Dad and to my mom that I regret terribly. I have hurt their feelings countless times," Ireland continued. "It isn't worth it. Don't dish s--tty things right back at them. Don't say things out of anger. You will get extremely annoyed with your parents. TRUST ME."
She also advises her new sister on drugs and alcohol: "Don't be that girl that get's wasted at parties and crawls on bathroom floors. It ain't cute. Luckily, I've never there, but I have gotten too drunk. Usually I would just pet people like farm animals and turn into a lesbotron and try to kiss a bunch of girls."
Ireland, often an over-sharer, doesn't stop there. She also warns Carmen about smoking weed at parties, telling her to do it "somewhere safe. With people you trust."
And if a guy is pressuring her about sex, the big sis warns "If you don't want to do it, say no. I'll probably be parked in a minivan outside of your parties with binoculars….So no funny business."
Read the TMI blog post in its entirety here >
SEE ALSO: Meet the beautiful young daughters of the Baldwin brothers