Co-sleeping is the sort of parenting topic which few mums and dads sit on the fence about.
For every parent who says it saved their sanity or was bonding, you'll have another who is staunchly against the practise.
Given the topic's divisiveness, how would you feel if you discovered your young child was co-sleeping with his dad and his dad's new partner whenever he stayed with them?
The mum in question feels like this crosses a line, and vented on Mumsnet .
Describing herself as being "absolutely livid" she explained: "He split two years ago and it was my decision and we have a four-year-old son that he has every other weekend.
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"I've just found out that not only has he still not mentioned her to me but my son has in fact met her several times and they all sleep in Daddy's bed.
"I don't know this woman, all I know is that she's about 21 years old and lives with her parents."
What appears to anger her the most is the fact her ex has not told her about his new partner.
She adds: "He definitely should have told me before introducing my son to her, let alone have them all sleep in the same bed."
In response to not being told about the new girlfriend, many mums pointed out this should be seen as a courtesy, and not a right.
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As for the bed sharing...
"F**k that don't let him go there till it stops," read one particularly blunt response.
Another mum pointed out, "I highly doubt it would be OK if it was the other way around! Or if you had a daughter sleeping in the same bed as your new boyfriend."
Agreeing, another mum added: "That’s completely inappropriate in my opinion and some random girlfriend or boyfriend of a parent should not be sharing a bed with someone else’s kid."
However, a lot of people didn't see what the big deal was.
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Perhaps the best piece advice came from one woman who wrote:
"I wouldn't be happy with my child sharing a bed with a virtual stranger either to be honest. However, if you trust him as a Dad and he normally makes sound parenting decisions then I would be inclined to trust him with this too.
"The most important person here is your son and you should chat to him about how he feels about this. Do it in a happy relaxed way and don't put words into his mouth or show him that you are angry."
