Final installment of how to interpret a British or Irish will with regard to land.
A fee tail estate is a tenure in land best suited to those with fruitful loins. When you die, the land goes to your children. And when they die, it goes to their children. It is therefore not recommended that you leave your 100 acre estate in the Cotswolds to your brother who's in the contemplative order of monks as a fee tail.
The most important thing to know about fee tail estates is that they only apply if you haven't already sired an heir. The words "to X and his children" are only fee tail if X hasn't got any children at the time of putting pen to paper. If X already has some kids, they get shares in the estate as fee simple benificiaries. This is known as the rule in Wild's Case.