BOSTON (NBC) — Hatchimals, one of many top-selling toys this holiday season, are allegedly having some foul-mouthed issues.

Parents have said the holiday’s hottest gift swears in its sleep.

Spin Master, the toy’s parent company, denied that the toys swear. Spokespeople said Hatchimals make unidentifiable noises when they “sleep.”

After about 30 minutes of attention, a furry toy is supposed to hatch from the plastic egg, then interact with kids.

Recently, parents have also complained that the toy is not “hatching” properly.

Some parents posted on social media to air their grievances with the best-selling toy.

Spin Master said it is staffing up its busy consumer hotline, and made an announcement to respond to consumer’s complaints:

“While the vast majority of children have had a magical experience with Hatchimals, we have also heard from consumers who have encountered challenges.”

Hatchimals were so popular over the holidays that even though they retailed for $60, many sold for hundreds online.

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