It's not uncommon for a will to leave property to a group of beneficiaries without actually naming each one. For example, someone might leave a gift—or an entire estate—to "my children" or "my surviving nieces and nephews." Because the beneficiaries aren't individually named, but are members of a certain class, lawyers call these "class gifts."
Generally, if a member of a group dies before the will-maker does, the property goes to the surviving members of the group, unless the will provides otherwise. For example, say Marcus uses his will to leave a piece of real estate to "my surviving brothers and sisters." The will doesn't name any alternate beneficiaries. When he signs his will, he has two brothers and two sisters still living. At his death, however, his brother Stephen has died, leaving two daughters of his own. The surviving brother and sisters inherit the real estate; Marcus's nieces, the children of his deceased brother, do not get a share.
If, however, the will had left the property to his siblings by name—"to Jacob Williams, Stephen Williams, Marcia Williams Hewitt and Juana Williams"—then the gift is not considered a class gift, and there might be a different result.
The state's "anti-lapse statute" might apply, and if it did, then Stephen's share would go to his daughters. Anti-lapse statutes presume that when you leave property to a close relative and that person dies before you do, you would want that person's children to inherit his or her share.
Every state except Louisiana has an anti-lapse statute. The various state laws are the same in broad outline, but differ in particulars.
Group gifts and anti-lapse rules are complicated. Gifts to groups of people often spawn confusion—or argument. If you don't know what the will-maker intended and can't figure out who should inherit a group gift, it's probably time to get professional advice from a probate lawyer.