I would tell her to Go Play! Don't allow her to sit with you. I used to have 2 boys that were like that. The second we went outside and I would sit and watch the kids they would immediately be around me. I would just tell them to go play and that they can't sit with me. At the beginning they would go sit on the play structure or sit on the ground but eventually they would get up with the other kids and go play. Right now I have a 2 year old that would also like to sit with me outside. I do the same thing with her and she goes with the others.