A bit clumsily, he tried to romp and gambol with her, as did Wolf.

He tried to interest her, as of yore, in following his lead in break-neck forest gallops after rabbits or in gloriously exhilarating swims in the fire-blue lake at the foot of the lawn.

To the pityingly on-looking Mistress and Master, he seemed like some general or statesman seeking to unbend in the games and chatter of a party of high school boys and girls.
But it was no use.
True, in the cross-country runs or the swirling charges after rabbits, neither Lady nor Wolf could keep up with Lad's flying stride.

And a long swim, which scarce breathed Lad, would exhaust either or both of them.
But, they were young; and he was middle-aged.

And, as in human relationships, that one sentence told the whole tragic story.
As well expect a couple of flyaway children to give up a game of tag in order to listen to the solemn discourse of an elderly uncle; as to make the fun-loving Lady and Wolf widen their selfish comradeship to include in it the steadier and older and infinitely wiser Lad.
Perforce, Lad was thrown more and more on the society of the Mistress and the Master.