Appropriateness of "putting my child down to sleep"

Putting your child to sleep is perfectly acceptable.

What your friend has gasped at is the use of the term "putting down" which means the euthanising of pets. "Putting to sleep" can also mean to euthanise but, in my experience, carries less of that connotation than "putting down".

If you do want to use the word down, you could say "laying my child down to sleep".

If you want to avoid the whole "putting to sleep" ambiguity altogether, you could say "putting my child to bed".

The whole idea of a euphemism is that you are replacing a description of something unpleasant with a description of something harmless. I think almost any phrase used as a euphemism is ambiguous in the sense that, if taken out of context, one could not be sure if it was being used literally or as a euphemism.

Think of other euphemisms. For example, we sometimes say a person "bought the farm" meaning that he died. But if you told me, "My brother always wanted to move to the country, and yesterday he finally bought the farm," I think I'd take it that you meant that he literally purchased a place for growing crops. We say two people "slept together" as a euphemism for having sexual relations. But if a mother says, "The baby has been sick so last night I slept with him to keep him quiet", I don't think I'd interpret that sexually. Etc etc.

I recall when I was a little boy we went on a family vacation and my father said that he was going to "see a man about a horse". I was all excited that we were going to go horseback riding ... until my mother explained that this was a euphemism for using a toilet.

Googling "put down to sleep" gives you an Urban Dictionary entry calling it an expression for euthanasia on the one hand, and hundreds of parenting sites using it for "putting your child to bed" on the other. Doctors use it:

While most babies less than six months who are put to sleep on their tummies or backs tend to stay there, many infants who are put down to sleep on their sides will change position, most of the time rolling onto their backs rather than onto their tummies.

Even a booklet on safe sleep co-produced by the Irish Health Service Executive and the Irish National Paediatric Mortality Register uses the phrase (5 times on 12 pages)!

Feel free to continue using the phrase, but I would prefer choosing a different wording myself, simply to avoid shocked reactions or needless discussions.

You all missed the point here. When the vet puts a pet “down” he doesn’t “put that pet down to sleep”. Neither he puts her “down the floor”.

He just “puts her down”, which means to kindly letting her die instead of suffering further.

Putting “down to sleep” has got nothing to do with putting a pet “down”. Hope it does make sense.