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Yup, perfectly normal - they hate to be "ignored" (where "ignored" can simply mean not being centre of attention or actively part of the conversation). Doesn't need to be visitors, can even be workmen!
I think it is lovely - really friendly. I too resort to TV (Shrek) if I really need DS to be amused.
I live on my own with my 3 year old consequently he is not short of attention. I find it difficult when I have a visitor or visitors without children. My child will try to gain their attention constantly and whilst I appreciate this is ok when the visitor first arrives it doesn't stop there. He will spend the evening showing them things, pulling me and generally trying to interrupt myself and the visitor. I have tried to settle him with a favourite toy or activity but he will not engage with it. The other night when this happened I put him on cbeebies (computer) I was so desparate but this is not an option I wish to fall back on.