What are 3 characteristics of an autosomal recessive trait in a pedigree?

Although an affected parent may potentially produce unaffected offsprings if mated with a homozygous to the dominant gene, I think this sentence is wrong because it's too general.

If I were you, I would replace it with:
If both parents are affected, they will produce only affected offsprings.
(That's because the affected parents with both be homozygous to the recessive allele, so all the offsprings will also be homozygous)

Or: Unaffected parents may produce affected offsprings. (you may also note that this is the usual case- when both parents are homozygous)


Other possible characteristics include:

if both parents are heterozygous, they have 25% probability to produce affected child.

Affected children are more frequent if the parents are consanguine (blood-relatives or whatever is that called. That's because, blood- relatives may share some common alleles.)