Personalized Half Marathon My 1st 13.1 Run Baby Bib. Cute half marathon running Baby Bib - White and Orange outfit says my 1st 13.1 run for girls. Our Baby Bib is rated high in convenience and durability and with a variety of fashionable colors, your baby can be trendy. Mix and match to any outfit. 100% cotton ring spun combed heather colors are cotton-poly. Width 7.75", Length 11.75"