Mouth sores/ulcers in both dc

[DextersMistress]

Ds2 (2) started complaining of a sore mouth 2 days ago. I looked and he had what looked like a cluster of small ulcers inside his bottom lip. Today ds1 (4) has complained of the same, and his mouth is covered in sores. Inside both cheeks and towards his throat. Ds2 has a couple more now too.

I know mouth ulcers are common in children but they're not contagious so I'm not sure. Any ideas please?

Primary herpes simplex, it can make them feel quite poorly so check for temperature and keep an eye on them. The other contender is hand ,foot and mouth, another common viral infection. If your worried see your GP.
Painkillers and soft diet.

Agree with Willdo.

Check hands and feets for spots/blisters. Can be elsewhere too (my dc had them on genitals, bottom, knees and elbows too but was definitely hand, foot and mouth).

Have checked their bodies, nothing there but I will look again tomorrow. No temperatures or other symptoms as yet just a very sore mouth. Sores don't look like ulcers, they're not blistered. More like mottled red spots.

Thanks, will keep an eye.