Bride bans sister in law from bridesmaid duties over fears her pregnancy will overshadow her

A bride-to-be is considering ditching her 16 year old sister-in-law as a bridesmaid after having fears that her pregnancy will overshadow her wedding. 
At the time of their wedding, the sister-in-law will have a 4 month old to care for.
“She’ll have a four-month-old to care for and it’s really not fair to expect father-in-law and mother-in-law to take on care duties while sister-in-law does bridesmaid stuff, it’s their son’s wedding.”
She added “Sister-in-law is still living in a fantasy world where she’ll be able to care for the child as a single parent and still live the life of a normal teenager  so I can’t ask her if she’ll manage it, she doesn’t know the reality of children yet.”
The bride adds that she is also worried about having the newborn baby around, saying it’d be a “massive elephant in the room.”
The bride ends by asking whether it’s ok for her to ask her pregnant sister-in-law not to be a bridesmaid and also posed the question if it was acceptable for her to ask that the baby not be at the wedding at all.
Users of the website Mumsnet did not hold back, branding her as “unreasonable” and even suggested that the bride was in need of a “reality check“ after her fears of being overshadowed.
Many users sympathised with the sister in law saying, “It sounds like you’re ashamed of having a 16-year-old mum as part of your wedding party. She will be having a hard enough situation without you ‘punishing’ her.”
Another user did not beat around the bush, letting the bride know what they really think. “It sounds like you wanted all the attention of getting married and then having the first grandchild and she has taken the attention from you.”
What do you think, is she being a bridezilla, or are her concerns justified?
Source: The Sun