Query from a settlement decree on the topic of Property Law

From a legally valid settlement decree, following is the clause of contention. It is complete in itself and there is no other information provided to draw any further conclusion Clause "That 1st floor shall be owned by Decree Holder and her husband as sole owner/landlord till they are alive and thereafter it shall be devolved upon all the sons equally." Question: 1) Does the above mentioned clause give the Decree Holder and her husband absolute right over the property to the extent that they could have executed a Will? 2) Subsequent to the death of the husband of the Decree Holder, could the Decree Holder have executed a Will to the extent of her share in the property? Or she could not have since the Decree Holder and her husband had only limited right in the property i.e. they were owners till they were alive and upon their death, the 1st floor should have devolved upon the three sons equally.