all growed up vs all grown up

Why are some native speakers using “all growed up” instead of the conventional “all grown up”?

There’s no such word as “growed”.

No, I don’t think so. “growed” sounds completely off.
Who is speaking like that? Maybe they are doing an impression of a foreigner?

My Australian friend does that and the famous Rugrats cartoon has an episode “All growed up”. You also can find it on tabloid websites (american ones I think).

It is playful and informal. It doesn’t intend to mock nonnative speakers.

Hi,

This expression ‘all growed up’ is said sometimes in an amusing way as if a child is saying it as a child would be following the pattern of making all past participles end in ‘(e)d’. It would be used when describing a child who looks ‘grown up’ as in: Here is a picture of young Charles, looking all growed up.

Alan