The relationship of pop princess Selena Gomez and ‘bad boy’ singer Justin Bieber has not always been smooth sailing and it seems the pair are now officially entering into a "serious" reunion. However, not everyone is happy with that: including the Naturally singer’s mother, Mandy Teefey.

Selena GomezSelena Gomez and Justin Bieber may be getting back together

TMZ reported that 41-year-old Mandy was hospitalised last week following a "heated" debate with her daughter about Selena and Justin giving their on-off relationship a go at being on again.

Their conversation caused Mandy to attend a hospital for a voluntary welfare check-up, it was reported.

Now the mother-and-daughter pair are believed to have unfollowed each other on Instagram.

According to TMZ, Selena's family will 'never forgive him or accept [Justin]' following their complicated split in 2014.

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The showbiz website has previously reported Justin is a 'huge trigger' for Selena's family and have reportedly said they intend to stay away from him.

The discussion reportedly became heated when Selena's mother learned how 'serious' the reunion was.

A source for Justin told the website he's aware Selena's family isn't happy with him, but he's determined to prove himself to them.

"He is sad that her mom is not doing well," the source added.

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This comes just three days after Mandy took to Instagram in memory of her other daughter, Scarlett, who she lost on December 17, 2011 due to a miscarriage.

Mandy penned the note on the anniversary of her miscarriage: "Thank you to all the fans who honored our Scarlett yesterday."

The 13 Reasons Why executive producer, wrote on her Instagram account on Saturday: "Dec 17 will never be the same, but we decide to celebrate her by writing her letters on red balloons and releasing them. Now the 17th is intertwined with the wrap of S2" - referring to season two of 13 Reasons Why.

Adding: "So, she was there in spirit as always. A mom's love for their children is pretty fierce. In order of my girls, Selena, Scarlett and Gracie."