Not silyl at all, but you needn't worry.On the application for my child's UK passport, I'm not sure if I should be using my maiden or married surname? Or just use both? US birth certificates only use a mother's maiden name. So I hesitated in filling out that portion of the application - don't want it to look like there are any discrepancies.
And another question regarding surnames and my visa application... the bio page of my passport uses my maiden name, but on one of the back pages it states that my passport was amended and my name has been changed to "blank" (I've always thought this looked a tad hokey). Do I fill out my application according to what is shown on my bio page, use both names, my married surname only.
Sorry, rather silly questions...
It doesn't really matter which name you use, as a name isn't material to either application, as they clearly relate to the same person.
For your son's passport application, just use your married name. You will probably enclosing your marriage certificate in any case.
Same with your spouse visa. While your passport still carries your maiden name, there is an observation that it has been changed. Again UKBA will know they belong to the same person as your marriage certificate is attached. Also on the application you have to state any previous names(s) you have been known by.