Ya tienen tres niñas, ojalá el próximo sea un niño.
vs.
Ya tienen tres niñas, ojalá el próximo será un niño.
Could both of these be correct? Or would it have to be the former simply because of the need for the subjunctive mood following ojalá? The english side of my brain wants the latter to be correct too... (something like "they already have three girls; hopefully the next one will be a boy.")