Nicki Minaj had guessed Rihanna was pregnant.
The 'Umbrella' hitmaker revealed earlier this week she is carrying her first child with boyfriend A$AP Rocky but her friend - who has a 16-month-old son with husband Kenneth Petty - recognised some signs the 33-year-old pop star was expecting before then.
Nicki said: "I had that vibe last time I was with them and I was saying some things.
"My son was loving her and she was so into the baby and looking back, that's what happens.
"You're more intrigued by little babies when you're about to have a baby."
Rihanna and Rocky announced their happy news in a series of pictures in which the 'Diamonds' singer showed off her bare bump, and Nicki praised the "iconic" photoshoot.
She is quoted by the Daily Star newspaper as saying: "She's beautiful. Everything she does, she does it in an iconic way and does everything on her own terms."
The 'Anaconda' singer doesn't think there's anything as satisfying as being a mother.
She gushed: "I'm happy for her because I know she's about to experience a different kind of joy - there's no words.
"When you do all this stuff, even if you're not a big star, when you put into the world as a woman, to me, that's your reward from the universe.
"It's something that will keep on giving. Every day, my son gives me a new gift. It's rewarding for me.
"So I'm happy for her."
It was previously claimed Rihanna is "so excited" to be pregnant and has embraced her changing shape.
A source said: "Having a baby is something she was never focused on, but being with Rocky opened her up to the idea. She couldn't be happier and is so excited to be a mom.
"She's loving all the changes to her body during pregnancy and has always celebrated pregnant women in her runway shows for Fenty."
