Mirra Andreeva, the youngest player in the WTA's top 300, qualified for the French Open main draw on Thursday and then hoped her older sister could make it a family double.
Andreeva, ranked 143, beat top seed in qualifying Camila Osorio of Colombia 7-6 (10/8), 6-4.
The Russian hit the headlines earlier in May when she reached the fourth round of the Madrid 1000 event where she turned 16.
On Friday, her 18-year-old sister Erika, ranked at 147, faces Serbia's Olga Danilovic.
"Its been one of our dreams to play a big tournament together," Mirra told rolandgarros.com.
"As all sisters we used to fight a lot over the smallest things, for the TV remote, who will switch the channel.
"Let's say now we're grown ups, we really appreciate each other and appreciate the time together on tour."
Also making the main draw for the French Open, which gets underway on Sunday, was Elizabeth Mandlik whose mother Hana Mandlikova was the women's singles champion in 1981.
American player Mandlik, ranked at 118, beat Laura Pigossi 6-2, 2-6, 7-5 to reach the main draw of a Slam for the third time.
Former world number 10 Lucas Pouille, whose ranking has slumped to 670 after a long battle with physical problems and depression, made the main draw of the men's event by seeing off Austria's Jurij Rodionov 1-6 , 7-5, 6-0.
"It's a great emotion, when I see all my family, my friends on the court. It's liberation," said Pouille, a semi-finalist at the Australian Open in 2019.
"It comforts me to know that I still have a lot of things to give and to do in this sport. I am extremely proud of myself, extremely happy today, for me, and for all the people who have been helping me for months trying to get back."