Theory:

“Never mind,” said Dad, Brushing the dirt
Off his hair and his face
And his trousers and his shirt,
 
“We’ll try Plan B. Stand;
 Out of the way!”
 Mum said, “Don’t fall;
 Again, O.K.?”
Explanation:
 
Stanza \(5\) elucidates the kid's father's pride once more. He didn't lose his confidence even after he fell. He got back up, dusting himself and his clothes. This attitude indicates that he will carry out a strategy to save the cat again and that he will never change his mind.
 
Dad's confidence.jpg
Dad's confidence
 
Stanza \(6\) describes how the kid's father appeared to be preparing to carry out plan B. He was planning to swung himself on a branch of the tree. And his adoring wife was once again warning him, protesting that he should not continue climbing up the tree because he may fall since the tree could not hold his weight.
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
Brushing
Cleaning away dirt and dust by scrubbing
2.
Protesting
To disagree with something very strongly
Reference:
National Council of Educational Research and Training (2007). Honeycomb. Dad and cat and the tree - Kit Wright (pp.107-109). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.