Singer-turned-fashion designer Jessica Simpson is known for her offbeat personality, but some people thought substances were to blame her peculiar behavior on HSN Thursday night. Simpson appeared to slur her words as she promoted her denim jean collection with her mother, Tina Simpson, on the shopping network.

As the designer talked about her “Kiss Me” Super Skinny Gray Jean, which retails for $59, she said that her sister, Ashlee Simpson, looks awesome in the neutral shade. She bopped around as she spoke and then made a strange comment about Ashlee Simpson and her husband, Evan Ross, sharing jeans.

Simpson, 35, has not responded to accusations that she was under the influence of drugs or alcohol during the “sell-a-thon.” Her reps did not respond to a request for comment either.

HSN, however, had nothing but positive things to say about the “With You” singer. "It was fun to have Jessica make her HSN debut with her mother, Tina, last night,” the network told People magazine in a statement Friday. “We were happy to host them and thrilled with the way customers responded to the collection." 

It's not the first time the petite businesswoman was accused of abusing drugs and alcohol. The starlet’s consumption of Adderall and alcohol is “out of control,” In Touch Weekly reported in April. The substance abuse has led her to act like “a train wreck” at interviews and events. “[Sister] Ashlee really called her out and told her she needed to get help, but Jessica freaked and ran out in tears. Now everyone’s on pins and needles about what to do,” the source told In Touch Weekly.

Since Simpson is reportedly in “complete denial” about her reputed problem, her mother, Tina, suggested they go to rehab together. “Going to rehab with Jessica means she can kill two birds with one stone,” a source told Life & Style in June. “Tina sees it as a win-win for mother and daughter.” The fashion designer got hooked on Adderall as a diet drug. “One minute she’s fine and the next minute she’s talking nonsense and acting all crazy,” a source said.

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