If you let it seed it will take over your garden, though it's easy to pull up when young as it develops quite long roots when older. Personally I wouldn't encourage it in any way 
I'm a bit suspicious of the assertion that it's biennial, the stuff that grows around my place (despite my annual eradication attempts) flowers in its first year.
What would you do if this was your cat?
The Government advice re emergency packs
What household chore have you got completely wrong?
Were you more emotionally attached to one parent over the other ?


