Question about my 18 month old's front chipped tooth...details inside...?

when my daughter's front tooth first started to come in, i noticed a reddish-pinkish line that ran straight down the center of it, i asked her dr. but he didnt really have aan answer for me, (im in the process of finding her a new pediatrician) but anyways, when her tooth got a little bigger the red line went away but the bottom of it chipped. now at 18 months old there is only half of the tooth left due to bumping it on my knee. Ive called to make a dentist appt but the soonest that they can see her is 3 weeks from now. Im just wondering if anyone knows what the dentist can do about it, if he will be able to cap it or if theyre just going to have to pull it, any help lease and thank you for taking the time to read this. =)