There is unlikely to be any record of her or relatives travelling to the UK, as incoming passenger lists do generally not include ship lists coming from Europe.
Look out for marginal notes (additional writing on the sides of birth documents, added later, as a reference to marriages, deaths, etc). e.g.
Marie Francoise Jeanne Fournet, daughter of François Fournet and Anne Bardou, married 7 Oct 1904 in Évran to Aimé Riquet - she was b. Dec 21 1882, and a marginal note on her birth shows both her marriage in 1904 and her death, 2nd April 1974, in Tours (which would make her the sister the family knew of in the 1960s).
If you want to look for relatives/people research the same family, try:
http://www.geneanet.org/The Côtes d’Armor archives also have "lists nominatives" (censuses) but they are not name indexed. There are about 70 pages per year and they do list the street name/area on the left hand margin. I checked every 5/10 pages until I found Bétineuc. (note that women are usually under maiden name even after marriage)
1891 - they are on page 21 of the census for Evran. Virginie and two older children (Henri 7 and Marie
with parents.
1896 - they are on page 40. Same family members as 1891
1901 - page 21 - parents and the two girls
(there are 1906 and 1911 censuses also available, and earlier ones, I only had a quick check)
