A group of 23 Hollywood moms who used the same sperm donor rented a vacation house and went on vacation together - but it's apparently not as weird as it sounds.  

It all began when Sarah Fain, a TV writer-producer for The Shield and The Vampire Diaries, turned to online sperm-donor browsing when she decided she wanted to be a single mom at 37-years-old.

"It's like online dating, only you don't have to have a relationship with the person," Fain told Hollywood Reporter. "It's not: 'What if this is the love of my life?' It's: 'This person doesn't have Alzheimer's in their genetic history.'"  

Fain picked out a sperm donor and after two years and nine rounds of intrauterine insemination (IUI) - where the ejaculation is "washed" to up the sperm quality before it is injected into the uterus - she gave birth to a girl named Violet. 

Fain first met one of the families she went on the vacation with when she brought Violet to a music class for toddlers. 

She noticed two women walk into the class with two boys around the same age as Violet, and one of them, oddly enough, looked familiar. 

When Fain went home that day she checked a Facebook group that was comprised with 15 families who also conceived with the same open donor. 

"There they were, [just a mile and a half away]," she recalled to Hollywood Reporter. 

Now Fain considers every member of that Facebook group her family and they all get together for dinner every Sunday. These weekly family dinners eventually led to them renting a vacation house for a family get-away together in September. There were 12 2-year-olds on the trip. 

"It's one of those things that feels incredibly bizarre for half an hour. Then it feels totally normal," Fain told Hollywood Reporter.  

Open sperm donations are growing in popularity, but there isn't a lot of research on babies who came from the sperm of the donor because so much secrecy surrounds these donations, according to the New York Times.