Family Planning by Frank Vickery
When young Tracy discovers she is pregnant, she doesn't know how to tell her parents - solid, dependable Elsie and hypochondriac Idris - or her boyfried, Bobby.
Gran, permanently in bed, knows all and sees all and helps pave the way for Tracy's announcement. Unfortunately, Idris, overhearing Tracy and Elsie, jumps to the wrong conclusion and believes he has only a short time to live!!
Feeling desperate, Idris confides in the next door neighbour, Maisie, who then takes advantage of Idris's vulnerable state and declares her long term yearning for him; after liberal measures of gin all round, she proceeds to demonstrate the intensity of her feelings for him just as his wife, Elsie, returns from a spot of hospital visiting! Things need to be sorted out.
Misunderstandings and mishaps abound, not least with Gran!!
This provides the nub of the comedy action that follows.