Morgan Eastwood & Tanner Koopmans
Clint Eastwood became a grandpa again when his daughter gave birth to a baby girl named Cleo in September.
Pauline Chalamet
The Sex Lives of College girls actress officially enrolled in mom life, announcing on Sept. 30 that she gave birth to her first child "three weeks ago."
Pauline, who is the sister of Timothée Chalamet, has not publicly disclosed the identity of her baby's father.
Colton Underwood and Jordan C. Brown
The Bachelor Nation star and his husband found baby bliss when they welcomed son Bishop Colton Brown-Underwood on Sept. 30.
Nina Agdal and Logan Paul
After the model gave birth to her and the YouTuber's first baby, she wrote on Instagram Sept. 29, "Esmé Agdal Paul has entered the chat."
Jack Grealish & Sasha Attwood
The England national team soccer star and his partner welcomed a new teammate—a baby girl named Mila Rose Grealish—on Sept. 27.
Frances Bean Cobain and Riley Hawk
The daughter of Kurt Cobain and the son of Tony Hawk welcomed a baby boy named Ronin Walker Cobain Hawk on Sept. 17.
Mandy Moore and Taylor Goldsmith
The This Is Us alum found herself with a Big Three of her own in September, when she and her husband welcomed daughter Louise Everett Goldsmith.
The baby girl joins older brothers August "Gus" Harrison and Oscar "Ozzie" Bennett.
John Mulaney and Olivia Munn
Everybody's in LA—including the couple's daughter Méi June Mulaney, who they welcomed via surrogate on Sept. 14.
"I am so proud of my little plum," Olivia—who also shares son Malcolm Hiep Mulaney with John—wrote on Instagram, explaining that her baby girl's name (pronounced May) is the Chinese word for plum. "My heart has exploded."
Jamie Otis and Doug Hehner
The Married at First Sight couple doubled their brood's size on Sept. 18, welcoming twin boys Hawkins Tyler Hehner—(born 6:05 p.m.—and Huxley James Hehner, who arrived three minutes later.
"Baby A was born normally. I pushed him out so fast, baby B was born BREECH," Jamie—who is also mom to daughter Henley Grace Hehner and son Hendrix Douglas Hehner—later wrote on Instagram. "It was a scary moment at first bc he was quite stunned and didn’t cry immediately but when he finally kinda 'came to' & I heard his little squeal I just lost it."
Grant Gustin and LA Thoma
The Flash alum and his physical therapist wife announced the birth of their son Arthur James Grant on Sept. 12, calling the baby boy their older daughter Juniper's new "best friend."
Cardi B and Offset
More than a month after filing for divorce, the "WAP" rapper gave birth to her third child with the Migos member Sept. 7. The former couple's older kids—daughter Kulture and son Wave—visited their new sibling in the hospital.
Ashley Tisdale and Christopher French
The High School Musical alum and her composer husband welcomed their second child, Emerson Clover French, Sept. 6.
Lala Kent
The Vanderpump Rules star became a mom of two on Sept. 3, when she gave birth to daughter Sosa—who she concieved through the use of a sperm donor and intrauterine insemination (IUI).
Her baby girl's arrival came three years after her breakup with Randall Emmett, with whom she shares older daughter Ocean.
Lea Michele and Zandy Reich
The Glee alum gave birth to her second child—named Emery Sol Reich—with the entrepreneur, writing on Instagram Aug. 25: "Our hearts are so full."
Brandon Jenner and Cayley Jenner
Meet the new Princess of Malibu! The reality star and his wife welcomed daughter Joan Almond Jenner in August."Born at home in a flash, just the most amazing experience for mama and baby girl," Brandon—who is also dad twin sons Bo and Sam as well as daughter Eva with ex Leah James—wrote on Instagram. "A beautiful, gentle birth. 9 lbs 2 oz, 21 1/2 inches long."
Mae Whitman
The Parenthood alum announced her journey into motherhood on Aug. 28, revealing that she named her baby boy after her former costar Miles Heizer.
Justin Bieber and Hailey Bieber
It's a baby, baby, baby, oh! The pop superstar and the Rhode Skin founder shared on Aug. 23 that they welcomed son Jack Blues Bieber.
Nelly and Ashanti
The "Body on Me" collaborators welcomed their first baby together—a son named Kareem Kenkaide Hayes—on July 18, their rep told E! News in August.
Parker McCollum and Hallie Ray Light
The country star welcomed a new gold chain cowboy when his wife gave birth son Major Yancey Tyler McCollum on Aug. 8.
Barbara Pierce Bush and Craig Coyne
Jenna Bush Hager announced on Aug. 5 that her twin sister gave birth to a baby boy named Edward Finn Coyne.
"My sissy had a little mister," the Today anchor wrote on Instagram, "and I fell madly in love with Edward Finn!"
Wayne Brady
On July 24, the Whose Line Is It Anyway? star revealed that he has a "6-month-old son that people don’t know about."
"It was not on my bingo card: 51-year-old dad—brand new kid," he continued, sharing that he welcomed baby boy Val Henry with an ex-girlfriend named Tina. "I didn’t see it coming."
Wiz Khalifa and Aimee Aguilar
The "See You Again" rapper—who shares son Sebastian Taylor with ex Amber Rose—privately welcomed a baby girl, Kadence, with girlfriend of five years Aimee Aguilar on July 17.
Ashley Iaconetti and Jared Haibon
Two years after welcoming son Dawson, the Bachelor in Paradise alums added to their brood with the July 22 arrival of their second baby boy Hayden Cruise Haibon.
Maks Chmerkovskiy and Peta Murgatroyd
The Dancing With the Stars couple welcomed their third son, Milan Maksim Chmerkovskiy, on July 12.