http://decision.tcc-cci.gc.ca/tcc-cci/decisions/en/item/73269/index.do 
McDermid v. The Queen (September 3, 2014 – 2014 TCC 264) was a case involving a taxpayer with two special needs children.
[18] Both children were given psychoeducational assessments by Dr. Piper and were found to have learning disabilities. The son was assessed in 2008 and again in 2010. The daughter was assessed in 2012. In addition, Dr. Piper filled out the DTC certificates in 2012.
[19] Dr. Horner, the family doctor, also filled out a DTC certificate, but his assessment was not detailed enough to be helpful in this proceeding.
[20] In 2010, Dr. Piper assessed the son (age 9 at the time) as having improved in many areas since the prior assessment in 2008. However, at age 9 the son continued to score very low in written language skills and auditory working memory. The auditory working memory problem made it difficult for the son to remember anything in sequence. Instructions needed to be kept very simple. The problem was illustrated by the son not being able to remember a coach’s instructions on a soccer field. I would also note that, based on a report by the son’s teacher, Dr. Piper concluded that the son had attention problems “high enough to warrant concern, although sub clinical.”
[21] In 2010, Dr. Piper assessed the daughter (age 7 at the time) as having low academic scores which evidenced a learning disability which could not be specified at her young age. It was also noted that the daughter had significant difficulties with stress. As for reports from the daughter’s teacher, all scores were within the normal range.
The court concluded that the son’s problems were severe enough to establish an entitlement to the disability tax credit but the evidence with respect to the daughter did not meet that threshold:
[24] Based on the evidence as a whole, I am persuaded that the son’s disability qualifies for the DTC, mainly due to the auditory working memory problem which required significant parental support. With respect to the daughter, I find that the evidence was not persuasive that her impairment in daily activities was severe enough to qualify for the DTC. Of course, this may change as the daughter becomes older and her daily activities become more complex.
[25] In light of these conclusions, the appeal will be allowed, but only with respect to the son’s disability. It remains to be considered which taxation years are affected.
[26] Ms. McDermid applied for the DTC for her son since birth. There is not a sufficient evidentiary basis to grant the DTC for years prior to the first assessment conducted by Dr. Piper in 2008. The son was in grade 1 at this time.
In light of the mixed success each party was to bear their own costs.