Singer Justin Bieber, who has re-entered Selena Gomez's life, is not the reason for the singer-actress' "family issues".
"Selena has always said that the one person that means the most to her is her mom, Mandy Teefey," a source told eonline.com.
"But still, they have had a really complicated relationship and have gone through a lot of ups and downs."
There was an "entire year," the source said, that Gomez and her mother didn't speak after the "Wolves" singer parted ways with Mandy as her manager in 2014.
"It caused a huge rift in their relationship. Mandy wouldn't even let Selena talk to her sister for a long time."
"Mandy and Selena's stepdad (Brian Teefey) really did everything they could for Selena so when she fired her it took a toll on Mandy emotionally and professionally," the source added.
In March 2017, Gomez and Mandy (who executive produces "13 Reasons Why") walked the red carpet together at the premiere of the drama.
A source previously said that Bieber has caused "so much angst" for Gomez's family and they are "very sad" she is back together with the singer.
But as the Gomez family continues to resolve their personal matters, a second source reveals it's Bieber that Gomez is leaning on.
"Selena is dealing with some family issues at the moment and Justin is there for her. He doesn't want to cause any problems between Selena and her mom... Justin and Selena are still togetherm" said the source.
The two singers confirmed their reconciliation in November.