The way they turned all the blame on the "unblushing Macdonald" was quite manipulating.
I think Laura is more like Marianne.
Sophia is the one who got caught while taking the 'fifth bank note' and it was Sophia who "happening one day to open a private drawer in Macdonals's libraray with one of her own keys" discovered them in the first place.
But Laura says nothing against it and even assists in 'blaming' Macdonald for accusing Sophia.
Perhaps Sophia is the one like Isabella.
The way she reacts when Laura is getting 'picturesque' verbally. Like Isabella not wanting to dance because her beloved James is not there - artifice in both their natures.